Scintillation proximity radioimmunoassay utilizing 125I-labeled ligands

Journal Article · Sun Dec 01 00:00:00 EST 1985 · Proc. Natl. Acad. Sci. U.S.A.; (United States)

DOI:https://doi.org/10.1073/pnas.82.24.8672· OSTI ID:5808400

Udenfriend, S; Gerber, L D; Brink, L; Spector, S

A unique type of radioimmunoassay is described that does not require centrifugation or separation. Microbeads containing a fluorophor are covalently linked to antibody. When an /sup 125/I-labeled antigen is added it binds to the beads and, by its proximity, the emitted short-range electrons of the /sup 125/I excite the fluorophor in the beads. The light emitted can be measured in a standard scintillation counter. Addition of unlabeled antigen from tissue extracts displaces the labeled ligand and diminishes the fluorescent signal. Application of scintillation proximity immunoassay to tissue enkephalins, serum thyroxin, and urinary morphine is described. Applications of the principle to study the kinetics of interaction between receptors and ligands are discussed.

• Research Organization: Roche Institute of Molecular Biology, Nutley, NJ
• OSTI ID: 5808400
• Journal Information: Proc. Natl. Acad. Sci. U.S.A.; (United States), Vol. 24
• Country of Publication: United States
• Language: English

Related Subjects

62 RADIOLOGY AND NUCLEAR MEDICINE
ENKEPHALINS
RADIOIMMUNOASSAY
MORPHINE
THYROXINE
IODINE 125
LABELLED COMPOUNDS
SCINTILLATION COUNTING
ALKALOIDS
AMINO ACIDS
ANALGESICS
AUTONOMIC NERVOUS SYSTEM AGENTS
BETA DECAY RADIOISOTOPES
CARBOXYLIC ACIDS
CENTRAL NERVOUS SYSTEM DEPRESSANTS
COUNTING TECHNIQUES
DAYS LIVING RADIOISOTOPES
DRUGS
ELECTRON CAPTURE RADIOISOTOPES
ENDORPHINS
HORMONES
IMMUNOASSAY
IMMUNOLOGY
INTERMEDIATE MASS NUCLEI
IODINE ISOTOPES
ISOTOPE APPLICATIONS
ISOTOPES
NARCOTICS
NEUROREGULATORS
NUCLEI
ODD-EVEN NUCLEI
OPIUM
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
ORGANIC IODINE COMPOUNDS
PEPTIDE HORMONES
PEPTIDES
POLYPEPTIDES
PROTEINS
RADIOASSAY
RADIOIMMUNOLOGY
RADIOISOTOPES
THYROID HORMONES
TRACER TECHNIQUES
550601* - Medicine- Unsealed Radionuclides in Diagnostics